Method of making motorcycle seat frame

ABSTRACT

A motorcycle seat is assembled from a metallic base, a separately formed back rest member of generally L-shaped configuration and a pair of generally L-shaped support rods. These are assembled with the support rods and horizontal portion of the back rest member disposed upon the upper surface of the base and secured thereto, and the rods are also secured to the upstanding portion of the back rest member. Cushion means is disposed upon the base and back rest members and includes a cover extending over the back rest member. The back rest member has a concave transverse cross section and is provided with a multiplicity of recesses in the rearward surface thereof in which buttons disposed on the rearward surface of the cover are substantially disposed.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a division of copending application Ser. No.827,542, filed Aug. 25, 1977, now U.S. Pat. No. 4,125,285, issued11-21-78.

BACKGROUND OF THE INVENTION

Owners of motorcycles frequently desire to customize the appearance oftheir vehicles or to improve the comfort provided by the seats. As aresult, they often purchase custom seat structures which meet their ownpersonal preferences. This has produced a demand for manufacturers ofcustom seats who in turn have been forced to increase the number ofmodels which they manufacture and inventory.

The situation with respect to those seats providing a back rest becomesparticularly acute in that the customary technique in forming the metalsupport structure has involved the stamping or bending of a single sheetof metal into a configuration providing both the base portion and theback rest portion. Even when substantial flanges and corrugations havebeen provided, there have been occasional problems with respect tomaintaining rigidity and structural strength. The preferred back restframe constructions presently employ support rods which are welded tothe seat or base portion and to the back rest portion so as to reinforcethe sheet metal structure; however, such assemblies encounter certainlimitations in design.

Another problem frequently encountered in seats having back reststructures is that of providing buttons upon the rear surface of theback rest to limit relative movement of the cover and to improve theappearance thereof. Such buttons have heretofore projected substantiallyoutwardly of the plane defined by the cover and have been susceptible toinadvertent engagement with other objects and resultant tearing from theback rest.

It is an object of the present invention to provide a method for makinga novel motorcycle seat including a back rest which is simple andeconomical and which provides a rugged and rigid structure.

It is also an object to provide such a method for making a seat assemblyin which the configuration and dimensioning of the components may bereadily varied, thus minimizing the required inventory of parts andincreasing the possible configurations resulting from severalcomponents.

SUMMARY OF THE INVENTION

It has now been found that the foregoing and related objects may bereadily attained in a method for making a motorcycle seat in which alength of sheet metal is formed into a base having a top wall and asidewall extending downwardly therefrom with the base having forward andrearward ends. A second length of sheet metal is separately formed intoa back rest member having a generally L-shaped configuration defined bya pair of arm portions with one arm portion being of relatively shortlength and narrow width and the other arm portion being of substantiallygreater length and width.

A pair of support rods are formed into generally L-shaped configurationwith the included angle thereof closely approximating the included angledefined by the back rest member. The rods and the back rest member aresecured to each other and to the upper surface of the top wall of thebase so that the wide arm of the back rest member and one arm of therods extend upwardly from the rearward end of the base and therelatively narrow arm of the back rest member and the other arm of therods extend forwardly along the top wall of the base. Cushion means arethen secured to the base and back rest member and include resilientmaterial on the upper surface of the base and the forward surface of theback rest member and a cover extending over the resilient material onthe base and over the upstanding portion of the back rest member.

In its preferred aspect, the back rest member is formed with the dimplesand apertures hereinbefore described and the buttons are seated in therecesses so as to lie substantially within the plane defined by themajor surface of the cover on the rearward surface of the upstandingportion of the back rest member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a motorcycle seat made in accordancewith the method of the present invention;

FIG. 2 is a plan view thereof with the resilient material and the coverbroken away so as to reveal underlying construction;

FIG. 3 is a side elevational view of the frame for the seat of FIG. 1;

FIG. 4 is a partially exploded view of the frame of FIG. 3 with theforward portion of the base broken away;

FIG. 5 is a fragmentary sectional view to an enlarged scale along theline 5--5 of FIG. 2;

FIG. 6 is a sectional view to an enlarged scale along the line 6--6 ofFIG. 2; and

FIG. 7 is an enlarged fragmentary cross section along the line 7--7 ofFIG. 1.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Turning now to the attached drawings in detail, FIGS. 1 and 2 illustratea seat embodying the present invention designed to seat both the driverand a passenger. As seen, the seat therefore includes a seat sectiongenerally designated by the numeral 10 comprised of the main seatportion 12 and the passenger seat portion 14 and it also includes a backrest portion generally designated by the numeral 16. As best seen inFIG. 2, the seat is provided by a frame assembly to be described ingreater detail hereinafter, upon which is supported resilient material20, such as a polyurethane foam, and encases by the cover 18 of flexiblematerial. A multiplicity of buttons 22 are provided on the back restsection 16, and simulated stitching 24 is utilized to provide anattractive appearance.

As seen in FIGS. 2-6, the frame assembly for the seat includes ametallic base generally designated by the numeral 26 and having a topwall 28 and sidewall 30 extending downwardly thereabout. The top wall 28is contoured during the forming operation so as to provide an elevatedpassenger portion 34 adjacent its rearward end, a main or driver portion36 at a lower level and an upwardly and rearwardly sloping transitionalportion 38. In addition, the contouring of the top wall provides anupstanding front lip portion 40 and an upstanding central portion 42 inthe transitional portion 38. Fasteners 44 (only in part shown) are usedfor securing the base 26 and thereby the seat to the chassis of themotorcycle.

The frame assembly also includes a generally L-shaped back rest membergenerally designated by the numeral 46 and having a horizontal portion48 of relatively short length and narrow width extending along the uppersurface of the passenger portion 34 of the top wall 28 of the base 26and extending somewhat rearwardly thereof as best seen in FIG. 3. Theback rest member 46 also has an upstanding portion 50 of substantiallygreater width and length than the horizontal portion 48 as is clearlyseen in FIGS. 2 and 4. The lower end of the upstanding portion 50 is ofsubstantially the same width as the rearward end of the base 26, and theupstanding portion 50 tapers to a reduced width at its upper end.

Each of a pair of generally L-shaped support rods generally designatedby the numeral 58 has an elongated generally horizontal portion 60extending along the horizontal portion 48 of the back rest member 46 andthe top wall 28 throughout the length of the passenger portion 34 andmost of the transitional portion 38. As seen, the dimensioning of thehorizontal portion 48 of the back rest member 46 and of the centralportion 42 of the top wall 28 of the base 26 is substantially the sameso that the support rods 58 extend along the opposite sides of thecentral portion 42. The support rods 58 also have an upstanding portion62 which extends along the front face of the upstanding portion 50 ofthe back rest member 46 throughout substantially its entire height.

The several elements of the frame assembly are secured together byweldments indicated by the numeral 56 which secure the support rods 58to the upstanding portion 50 of the back rest member 46 and to thehorizontal portion 48 of the back rest member 46 and to the top wall 28of the base 26, thus providing a rigid assembly.

Extending about the side and upper edges of the upstanding portion 50 ofthe back rest member 46 and about the edges of the sidewall 30 of thebase 26, are channel-shaped protector strips 52 and 32, respectively, ofsynthetic resin which provide a smooth relatively low abrasion edgesurface for forming the cover 18 thereabout. In addition, the base 26has apertures 64 spaced along the side and front margins thereof forreceiving rivets (not shown) inserted through the cover 18 on theundersurface thereof so as to secure the cover 18 thereto.

As best seen in FIGS. 6 and 7, the upstanding portion 50 of the backrest member 46 is formed so as to be concavely arcuate in its transversedimension, thus providing an arc which opens forwardly of the seat anddefines a recess at least substantially equal in depth to the diameterof the support rods 58. In addition, the upstanding portion 50 isprovided with a series of spaced apertures 66 and the metal thereaboutis deformed forwardly so as to provide dish-shaped recesses or dimples68 opening rearwardly of the back rest member 46.

Inserted into the apertures 66 are insert elements 70 having aperipheral collar 72 which seats in the recess of dimple 68 and aresiliently deformable shank 74 which extends through the aperture 66and engages therein. Upon assembly of the cover 18, onto the back restmember 46, a button 76 having a stem 78 of wire or the like is disposedover the insert element 70 and its stem 78 is passed through an aperturein the cover 18 and through the core of the insert element 70 so as toproject into the resilient material 20. Another button 22 having asimilar stem 78 is placed upon the front surface of the cover 18 inalignment therewith, and the two stems 78 are tightly drawn and securedtogether by a cord 80. Thus, it can be seen that the button 70 on therear surface of the back rest portion 16 does not project substantiallybeyond the plane of the surrounding cover 18, thus minimizing thelikelihood that it will be caught and inadvertently torn therefrom.

In assembling the seats of the present invention, the base 26 is formedfrom sheet metal so as to provide the various contours in the top wall26 thereof and so as to form the sidewall 30 and front lip portion 40.The various apertures 64 for the rivets and the apertures for thefasteners 44 are also formed therein.

The back rest member 46 is separately formed in its L-shapedconfiguration and the apertures 66 and dimples 68 are convenientlyformed as a part of a single punching operation. Similarly, the supportrods 58 are formed into their L-shaped configuration conformingsubstantially to the included angle between the horizontal portion 48and the upstanding portion 50 of the back rest member 46.

The several elements thus formed are conveniently assembled in a jig sothat the support rods 58 extend along the side margins of the horizontalportion 48 of the back rest member 46 and of the central portion 42 ofthe base 26. A series of weldments 56 are then made so as to secure theseveral components in rigid assembly.

Following this assembly, the protective strips 32,52 are slipped overthe edges of the base 26 and back rest member 46. The insert elements 70are inserted into the apertures 66 and seated therein with the collars72 disposed within the dimples 68.

In the next step, the resilient material 20 is disposed over the uppersurface of the base 26 and the forward surface of the back rest member46, and the back rest portion of the cover 18 is slid downwardly overthe back rest member 46 and its associated resilient material 20. Theportion of the cover 18 encasing the seat section 10 is then formedabout the resilient material 20 and folded under the base member 26 andsecured thereto by rivets (not shown) seated in the apertures 64.

The buttons 76 are then secured to the back surface of the back restportion 16 by inserting the stems 78 through apertures in the cover 18and through the cores in the shanks 74 of the insert elements 70.Similar buttons 76 are aligned on the front surface of the back restsection 16 and cords 80 are looped about the cooperating stems and usedto draw the buttons of each cooperating pair tightly together and tosecure them in position.

Since the back rest member is separately formed from the base, it can beseen that a single base can be used with various configurations andsizes of back rest members, thus minimizing inventory requirements andpermitting greater flexibility in design. Moreover, the formation of theback rest member as a separate element also permits elimination ofunnecessary material and scrap and it also permits facile formation ofthe back rest member with the highly desirable concave recesses anddimples to facilitate formation of the seat assembly.

Still another advantage is obtained by having the horizontal portion ofthe back rest member overlap the top surface of the base, therebyproviding a highly rigid assembly in combination with the support rods.

It will be appreciated that both the base and the back rest member mayhave configurations and dimensions differing significantly from thosespecifically illustrated. It will also be appreciated that the supportrods may extend even further along the top surface of the base.Moreover, if so desired, additional support rods may be employed and therods may be formed of rectangular bar stock rather than the cylindricalstock. It will also be appreciated that various mechanical fasteners maybe used in conjunction with, or in place of, the weldments to secure theseveral components in rigid assembly.

1. In a method for making a motorcycle seat, the steps comprising:A.forming a length of metal sheet into a base having a top wall and asidewall extending generally downwardly therefrom, said base havingforward and rearward ends; B. forming a length of sheet metal into aback rest member having a generally L-shaped configuration defined by apair of arm portions, one arm portion being of relatively short lengthand of relatively narrow width and the other arm portion being ofsubstantially greater length and width; C. forming a pair of supportrods into a generally L-shaped configuration, the included angle thereofclosely approximating the included angle of the L-shaped configurationof said back rest member; D. securing said rods and back rest member toeach other and to the upper surface of said top wall of said base sothat said other arm portion of said back rest member extends upwardlyfrom the rearward end of said base and said one arm portion of said backrest member extends forwardly thereof, said rods extending forwardlyalong the forward face of said back rest member other arm portion andbeing secured thereto; and E. securing cushion means to said base andback rest member including disposing resilient material on the uppersurface of said base and the forward surface of said back rest memberother arm portion and providing a cover extending over said resilientmaterial on said base and about said back rest member.
 2. The method inaccordance with claim 1 wherein said back rest member other arm portionis formed so as to have an arcuate transverse cross section with the arcopening forwardly of said seat.
 3. The method in accordance with claim 1wherein said back rest member other arm portion is formed with amultiplicity of generally forwardly projecting bosses defining forwardlyopening recesses therewithin.
 4. The method in accordance with claim 3including the steps of providing apertures in said back rest memberother arm portion, forming inserts having recesses opening at one endthereof, and inserting the other end of said inserts into said aperturesof said back rest member other arm portion to provide said bosses. 5.The method in accordance with claim 3 wherein there is included the stepof affixing buttons on the face of said cover by inserting shankportions on said buttons into said recesses of said bosses.
 6. Themethod in accordance with claim 1 wherein said rods and back rest memberare secured to each other and to said base by welding.